What pressure must a spring buoy, moored at a 500 foot depth, withstand?

Correct Answer: Option C — 225 psig

Hydrostatic pressure increases at a standard rate of approximately 0.445 psi per foot of saltwater depth. At 500 feet, the total external pressure exerted on a submerged spring buoy equals 500 multiplied by 0.445, totaling roughly 225 psig.